The Existence of Huge Channels That Look Like Dry Riverbeds

question 26

Multiple Choice

The existence of huge channels that look like dry riverbeds on Mars is strong evidence that it ____.

• A) has ocean basins and continents
• B) had a Martian civilization that used irrigation
• C) had a warm climate in the past
• D) has a dense earth-like atmosphere
• E) is much younger than Earth

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Definitions:

Concentration Gradient

A variation in the concentration of a substance across a distance, often leading to the diffusion of substances from an area of higher concentration to an area of lower concentration.

Diffusion

Spontaneous spreading of molecules or atoms through a fluid or gas.

Indigestible Substances

Materials that cannot be broken down and absorbed by the digestive enzymes and system of an organism, often passing through the system largely unchanged.

Entropy

Measure of how much the energy of a system is dispersed.